To solve a problem that the network lifetime is shortened by performing routing such that power is not consumed in a terminal having much dump power.
Each terminal has a transmitting/receiving function 10, and a data processing function 11 performing required processing by identifying data. An operation schedule period holding function 14 holds an operation schedule period, an elapsed time calculating function 15 calculates lapsed time after starting operation of its own terminal, and an elapsed time holding function 16 holds the elapsed time calculated by the elapsed time calculating function 15. A residual operation period calculating function 17 calculates a residual operation period, and a residual operation period holding function 18 holds that residual operation period. Each terminal has a function 19 for detecting residual power in its terminal and that residual power is held by a residual power holding function 20. A dump power calculating function 23 calculates damp power from the residual operation period, residual power, and the like, and that power is held by a holding function 24.
JOCHA TAKESHI
HIRANO YOSHITAKA
Uzawa Hidehisa